Electrochemical sensor based on a silver nanowires modified electrode for the determination of cholesterol

In this study, the fabrication of an amperometric cholesterol biosensor based on silver nanowires (AgNWs) and cholesterol oxidase (ChOx)-graphene oxide (GO)-chitosan (CS) film is reported. The electrochemical behaviour of the ChOx/Ag/GO/CS/ITO biosensor was studied using cyclic voltammetry (CV), which revealed that the developed biosensor possessed high sensitivity (13.628 mu A mM(-1) cm(-2)) and a low detection limit (0.427 mg dL(-1)). The apparent Michaelis-Menten constant, K-M(app), of this biosensor was very low (2.813 mM), originating from the effective immobilization process and the nanowires structure of the substrate. The biosensor expressed a wide linear range up to 400 mg dL(-1) in physiological conditions (pH 7.0), making it very promising for the clinical determination of cholesterol.